* Will have the best performance, as it doesn't have much extra code apart from the server itself.
    * You wouldn't write an application in Uvicorn directly. That would mean that your code would have to include more or less, at least, all the code provided by Starlette (or **FastAPI**). And if you did that, your final application would have the same overhead as having used a framework and minimizing your app code and bugs.

### Restart After Crash

But in those cases with really bad errors that crash the running **process**, you would want an external component that is in charge of **restarting** the process, at least a couple of times...

!!! tip

    If you have an older version, you would get errors when trying to use `Annotated`.

    Make sure you [Upgrade the FastAPI version](../../deployment/versions.md#upgrading-the-fastapi-versions){.internal-link target=_blank} to at least 0.95.1 before using `Annotated`.

### Import `Depends`

=== "Python 3.10+"

    ```Python hl_lines="3"
    {!> ../../../docs_src/dependencies/tutorial001_an_py310.py!}
    ```

=== "Python 3.9+"

Still, in both situations, chances are that **FastAPI** will [still be faster](index.md#performance){.internal-link target=_blank} than (or at least comparable to) your previous framework.

### Dependencies

                "msg": "String should have at least 1 character",
                "type": "string_too_short",
                "input": "",
            }
        )
        # TODO: remove when deprecating Pydantic v1
        | IsDict(
            {
                "ctx": {"limit_value": 1},
                "loc": ["query", "foo"],
                "msg": "ensure this value has at least 1 characters",

    if origin is Union or origin is UnionType:
        at_least_one_scalar_sequence = False
        for arg in get_args(annotation):
            if field_annotation_is_scalar_sequence(arg):
                at_least_one_scalar_sequence = True
                continue
            elif not field_annotation_is_scalar(arg):
                return False
        return at_least_one_scalar_sequence

                    "msg": "String should have at least 2 characters",
                    "input": "f",
                    "ctx": {"min_length": 2},
                }
            ]
        }
    ) | IsDict(
        {
            "detail": [
                {
                    "loc": ["path", "item_id"],
                    "msg": "ensure this value has at least 2 characters",

But it's not possible to have a running container without **at least one running process**. If the main process stops, the container stops.

## Build a Docker Image for FastAPI

Okay, let's build something now! 🚀